<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域 -->
    <el-card>
    <!-- 头部警告区域 -->
      <el-alert show-icon title="注意：只允许为第三级分类设置相关的参数！" type="warning" :closable="false"></el-alert>
      <!-- 选择商品分类区域 -->
      <el-row>
        <el-col>
          <span>选择商品分类:</span>
          <!-- 选择商品分类的级联选择框 -->
            <el-cascader v-model="selectedParamsKeys" :options="paramsList" :props="paramsProps"
                         @change="handleChange"></el-cascader>
            </el-col>
      </el-row>
      <!-- tab页面区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态属性" name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addParamsDialogVisible = true">添加参数</el-button>
          <!-- 动态参数的表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item , i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">{{item}}</el-tag>
                <!-- 输入文本框 -->
                <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                          ref="saveTagInput" size="small" @keyup.enter.native="handleInputConfirm(scope.row)"
                          @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="#"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态参数的面板 -->
        <el-tab-pane label="静态属性" name="only">
          <!-- 添加参数的按钮 -->
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addParamsDialogVisible = true">添加属性</el-button>
          <!-- 静态参数的表格 -->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item , i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">{{item}}</el-tag>
                <!-- 输入文本框 -->
                <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                          ref="saveTagInput" size="small" @keyup.enter.native="handleInputConfirm(scope.row)"
                          @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加的按钮 -->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index" label="#"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加参数的对话框 -->
    <el-dialog :title="'添加' + titleText" :visible.sync="addParamsDialogVisible"
               width="50%" @close="addDialogClose">
      <!-- 添加参数的对话框 -->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addParamsDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 编辑参数的对话框 -->
    <el-dialog :title="'编辑' + titleText" :visible.sync="editParamsDialogVisible"
               width="50%" @close="editDialogClose">
      <!-- 编辑参数的对话框 -->
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editParamsDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 删除参数的对话框 -->

  </div>
</template>

<script>
  export default {
    name: "Params",
    data() {
      return {
        // 商品分类列表
        paramsList: [],
        // 级联选择框的配置对象
        paramsProps: {
          value: 'cat_id',
          label: 'cat_name',
          children: 'children'
        },
        // 级联选择框双向绑定的数据
        selectedParamsKeys: [],
        // 被激活的页签的名称
        activeName: 'many',
        // 动态参数的数据
        manyTableData: [],
        // 静态参数的数据
        onlyTableData: [],
        // 控制添加参数对话框的显示与隐藏
        addParamsDialogVisible: false,
        // 添加参数的表当数据对象
        addForm: {},
        // 添加表单的验证规则对象
        addFormRules: {
          attr_name: [
            {
              required: true, message: '请输入参数名称', trigger: 'blur'
            }
          ]
        },
        // 控制编辑对话框的显示与隐藏
        editParamsDialogVisible: false,
        // 修改的表单数据对象
        editForm: {},
        // 编辑表单的规则验证对象
        editFormRules: {
          attr_name: [
            {
              required: true, message: '请输入参数名称', trigger: 'blur'
            }
          ]
        },
      }
    },
    created() {
      this.getParamsList()
    },
    methods: {
      // 获取所有的商品分类列表
      async getParamsList() {
        const { data: res } = await this.$http.get('categories')
        if (res.meta.status !== 200) {
          return this.$message.error('获取商品分类失败！')
        }
        this.paramsList = res.data
      },
      // 级联选择框选中变化，会触发这个函数
      handleChange() {
        this.getParamsData()
      },
      // tab页签点击事件的处理函数
      handleTabClick() {
        this.getParamsData()
      },
      // 获取参数的列表数据
      async getParamsData() {
        // 证明选中的不是三级分类
        if (this.selectedParamsKeys.length !==3) {
          this.selectedParamsKeys = []
          this.manyTableData = []
          this.onlyTableData = []
          return
        }
        // 根据所选分类的Id,和当前所处的面板，获取对应的参数
        const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, {params: { sel: this.activeName }})
        if (res.meta.status !== 200) {
          return this.$message.error('获取数据失败！')
        }
        // 渲染参数下的可选项
        res.data.forEach(item => {
          item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
          // 控制文本框的显示与隐藏
          item.inputVisible = false
          item.inputValue= ''
        })
        // 判断是动态数据还是静态数据
        if (this.activeName === 'many') {
          this.manyTableData = res.data
        } else {
          this.onlyTableData = res.data
        }
      },
      // 监听添加参数对话框的关闭事件
      addDialogClose() {
        this.$refs.addFormRef.resetFields()
      },
      // 点击按钮添加参数
      addParams() {
        // 表单预验证
        this.$refs.addFormRef.validate( async valid => {
          if (!valid) {
            return
          }
          const { data: res} = await this.$http.post(`categories/${this.cateId}/attributes`,  {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          })
          if (res.meta.status !== 201) {
            return this.$message.error('创建参数失败！')
          }
          this.$message.success('创建参数成功！')
          // 关闭添加参数的对话框
          this.addParamsDialogVisible = false
          // 刷新数据
          this.getParamsData()
        })
      },
      // 点击按钮展示对话框
      async showEditDialog(attr_id) {
        // 获取当前参数信息
        const { data: res } = await this.$http.get(`categories/${ this.cateId }/attributes/${attr_id}`, { params: { attr_sel:this.activeName }} )
        if (res.meta.status !== 200) {
          return this.$message.error('获取数据失败！')
        }
        this.editForm = res.data
        this.editParamsDialogVisible = true
      },
      // 监听编辑对话框的关闭事件,重置修改的表单
      editDialogClose() {
        this.$refs.editFormRef.resetFields()
      },
      // 点击按钮，保存修改参数信息
      editParams() {
        // 表单预验证
        this.$refs.editFormRef.validate( async valid => {
          if (!valid) {
            return
          }
         const { data: res } = await this.$http.put(`categories/${ this.cateId }/attributes/${ this.editForm.attr_id }`, { attr_name:this.editForm.attr_name, attr_sel: this.activeName})
          if (res.meta.status !== 200 ) {
            return this.$message.error('修改参数失败！')
          }
          this.$message.success('修改参数成功！')
          // 刷新数据列表
          this.getParamsData()
          this.editParamsDialogVisible = false
        })
      },
      // 删除参数
      async removeParams(attr_id) {
        const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).catch(err => {
          return err
        })
        if (confirmResult !== 'confirm') {
          return this.$message.info('已取消删除！')
        }
        const { data: res } = await this.$http.delete(`categories/${ this.cateId }/attributes/${ attr_id}`)
        if (res.meta.status !==200) {
          return this.$message.error('删除参数失败！')
        }
        this.$message.success('删除参数成功！')
        // 刷新数据列表
        this.getParamsData()
      },
      // 文本框失去了焦点，或者按下了Enter都会触发
      async handleInputConfirm(row) {
        // .trim()去除文本框两端的空格
        if (row.inputValue.trim().length === 0) {
          row.inputValue = ''
          row.inputVisible = false
          return
        }
        // 用户输入真实的内容
        row.attr_vals.push(row.inputValue.trim())
        row.inputValue = ''
        // 隐藏输入框
        row.inputVisible = false
        // 发起网络请求，把数据保存到数据库
        this.saveAttrVals(row)
      },
      // 将对attr_vals的操作，保存到数据库中
      async saveAttrVals(row) {
        // 发起网络请求，把数据保存到数据库
        const { data: res } = await this.$http.put(`categories/${ this.cateId }/attributes/${ row.attr_id }`,
            { attr_name: row.attr_name, attr_sel: row.attr_sel, attr_vals: row.attr_vals.join(' ')})
        if (res.meta.status !== 200) {
          return this.$message.error('修改参数项失败!')
        }
        this.$message.success('修改参数项成功！')
      },
      // 点进按钮显示文本输入框
      showInput(row) {
        row.inputVisible = true
        // 让文本框自动获得焦点
        // $nextTick方法的作用，就是当页面上元素被渲染之后，才会指定回调函数中的代码
        this.$nextTick(_ => {
          this.$refs.saveTagInput.$refs.input.focus();
        })
      },
      // 删除对应参数下的可选项
      handleClose(i, row) {
        // splice(i, 1)删除i索引下的余项
        row.attr_vals.splice(i, 1)
        this.saveAttrVals(row)
      }
    },
    computed: {
      // 如果按钮需要被禁用，则返回true,否则返回false
      isBtnDisabled() {
        if (this.selectedParamsKeys.length !== 3) {
          return true
        }
        return false
      },
      // 当前选中的三级分类的Id
      cateId() {
        if (this.selectedParamsKeys.length === 3) {
          return this.selectedParamsKeys[2]
        }
        return null
      },
      // 动态计算标题的文本
      titleText() {
        if (this.activeName === 'many') {
          return '动态参数'
        }
        return '静态属性'
      }
    }
  }
</script>

<style scoped>
  .el-alert {
    margin-bottom: 15px;
  }
  .el-tag {
    margin: 10px;
  }
  .input-new-tag {
    width: 100px;
  }
</style>